Weeks-Long I-5 Shutdown Through Portland Set to Begin September 11

Commuters across the metro suburbs — Beaverton, Gresham, Lake Oswego, West Linn, and Clackamas — should start planning now for a major disruption to the region's main north-south freeway. Starting September 11, all southbound lanes of I-5 between I-405 and I-84 will close for up to five weeks, running 24 hours a day, seven days a week.

The closure also takes out the I-5 southbound connector to I-84 and several on/off-ramps near the Rose Quarter, including Alberta Street, Greeley Avenue, and the Moda Center access ramps. It's tied to Phase 1A of the I-5 Rose Quarter Improvement Project, a stormwater, bridge, and auxiliary-lane construction effort that's part of a larger $2 billion undertaking.

The numbers are significant: roughly 120,000 vehicles use this stretch of I-5 daily, including nearly 12,000 trucks. Oregon DOT is warning drivers to expect commutes two to three times longer than normal, with congestion likely to spill onto local streets and even across the river into Washington.

For anyone commuting from the suburbs into downtown Portland or beyond, the state's official detour routes southbound traffic onto I-405, while pushing regional through-traffic to I-205 — meaning drivers from West Linn, Lake Oswego, and Clackamas who already lean on I-205 should brace for extra congestion there too.

A few alternatives worth considering before September 11: TriMet's MAX Yellow Line runs every 15 minutes and connects to park-and-ride lots at Delta Park/Vanport and the Expo Center, BIKETOWN rentals are an option for shorter downtown trips, and C-TRAN offers additional bus service for anyone crossing from the Washington side.

With the closure just under a month out, now's the time to test alternate routes or transit options before the detours become the daily norm.